JPH0317445B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION "Field of Industrial Application" The present invention is applicable to a passenger vehicle comprising, for example, a planting section having a seedling stand and a planting claw, and a riding section consisting of an agricultural tractor or a vehicle dedicated to rice planting. In the rice transplanter, the planting section is installed in the riding section so as to be able to be raised and lowered via a planting section support member such as a three-point link mechanism, and the planting section is raised and lowered to adjust the depth of seedling planting using the planting claws. This invention relates to a device that maintains a substantially constant state.

``Prior art'' As shown in Japanese Utility Model Application Publication No. 50-132525, there is a technique in which a sensor is installed to detect changes in the load at the planting area and the ground pressure of the float is adjusted to keep the planting depth approximately constant. Ta.

"Problems to be Solved by the Invention" In the prior art, the load reference value of the planting section cannot be changed during the planting operation, so even if the field hardness changes during the planting operation, the load before the change The sensor output is judged based on a reference value, and there have been problems in handling and functionality, such as the planting depth being easily changed due to changes in field hardness.

"Means for Solving the Problems" However, the present invention provides a device in which a planting section is installed so that it can be raised and lowered by a planting section support member, and a load sensor that detects changes in the load on the planting section; The invention is characterized in that it is provided with a manual operation tool for changing the load reference value of the section.

``Effect'' Therefore, even if the field hardness changes, the operator in the driver's seat operates the manual operating tool to change the load reference value, so the sensor output can always be judged appropriately. This makes it possible to prevent the planting depth from being changed due to changes in field hardness, and it can be handled more safely than in the past, and the sensor detection function can be easily improved. ``Example'' Examples of the present invention will be described in detail below based on the drawings. Fig. 1 is a schematic side view of the riding rice transplanter, and Fig. 2 is the same plane.
Reference numeral 5 denotes a connection frame that connects the front and rear vehicle bodies 2 and 3 so as to be bendable only in the horizontal direction via a pivot shaft 6;
7 and 8 are front and rear wheels for paddy fields that are attached to the left and right sides of the front and rear vehicle bodies 2 and 3 via swing cases 9 and 10;
12 is a preliminary seedling stand supported by the pillar 11; 13 is a driver's seat attached to the upper part of the rear of the front vehicle body 2 via the pillar 11; A turning handle 15 is provided at the upper front part, and 15 is an engine mounted on the rear vehicle body 3.

In addition, 16 in the figure is a six-row planting plant that is installed in the front part of the front vehicle body 2 via a three-point linkage mechanism 17 so as to be able to be raised and lowered, and 18 is a seedling with a low front and rear height that is moved back and forth from side to side. 19 is a planting claw for taking out and planting one seedling from the front vehicle seedling mounting platform 18; 20 is a transmission case to which the seedling mounting platform 18 and the planting claw 19 are attached; 2;
1 is a float supporting the transmission case 20, 22
2 is a front bumper attached to the transmission case 20;
3 is a fixed frame that supports each transmission case 20...
The seedling platform 18 and the planting claws 19 are appropriately driven via the PTO transmission shaft 24 to continuously plant seedlings.

The three-point link mechanism 17 consists of a pair of lower links 25 and top links 26. One end of the lower link 25 is pivotally connected to the lower surface of the front vehicle body 2 through a pin 27, and the other end of the lower link 25 is pivotally connected to the lower end of the fixed frame 23 through a pin 28. At the same time, the other end of the top link 26 , which is a planting part support member whose one end is connected to the upper end of the fixed frame 23 via a pin 29 , is connected to the link mechanism 30 .

A lateral vibration prevention spring 32 is mounted between the lower end of the fixed frame 23 and the bracket 31, and a lift arm 33 whose one end projects forward of the front vehicle body 2 is connected to the middle of the lower link 25 via a connecting rod 34. It is configured to move the planting section 16 up and down by swinging the lift arm 33 using hydraulic pressure.

As shown in FIG. 3, the long hole 3 at the lower end of the connecting rod 34 is inserted into the planting pin 35 on the intermediate side surface of the lower link 25.
6 is engaged, and a spring 37 is stretched between the lower link 25 and the lift arm 33 in parallel with the connecting rod 34, and the float 21 is placed in the field under a standard load state with a certain amount of seedlings placed on the seedling stand 18. The float 21 is sunk to a certain depth on the surface, and is formed so that the grounding pressure of the float 21, that is, the grounding load of the float 21 and the tension spring force of the spring 37 are balanced. Further, a piston rod 39 of a hydraulic cylinder 38, which is a support height adjustment member attached to the front vehicle body 2, is connected to the lift arm 33. A hydraulic pump 40 that operates in conjunction with the engine 15 is communicated with the cylinder 38 via a 4-port 3-position hydraulic switching valve 41 operated by a manual lever 41a.
3 and rotate the top ring 2 upward.
6, the pump 40 is connected to the switching valve 41 and the back pressure regulating valve 4.
2, the lift arm 33 is fixedly supported, and the pump 40 is connected to the tank 43 via the switching valve 41 and the valve 42, and the switching valve 41 and the valve 42 are connected to the tank 43 through the switching valve 41 and the valve 42.
The lift arm 33 is configured to be vertically rotated via the cylinder 38 in response to the opening and closing of the valve 42 by communicating the valve 42 with the cylinder 38 through the variable throttle valve 44 and the switching valve 41.

Further, a switching valve 45 is provided to short-circuit between the hydraulic switching valve 41 and the back pressure adjustment valve 42 to the oil tank 43,
The adjustment operation by the valve 42 can be canceled by operating the lever 45a of the switching valve 45.

As shown in FIG. 4, the back pressure regulating valve 42 has an operating shaft 46 slidably inserted into the valve 42, and a coupling bolt 47 is screwed onto the outer end of the shaft 46 that protrudes outward from the valve 42. are doing.

Further, a pressure reducing valve 50 is provided at the other end of the shaft within the valve 42 via a pressure reducing spring 49.
A high pressure oil line 51 and a low pressure oil line 52 are connected to the valve 42.
The high pressure oil pipe 51 is connected to the switching valve 41 and the throttle valve 44, and the low pressure oil pipe 52 is connected to the tank 43.
At the same time, a pressure reducing valve 50 is incorporated to control the communication between the high pressure oil line 51 and the low pressure oil line 52, and the back pressure chamber 53 of the low pressure oil line 52 and the pressure reducing valve 50 is connected to each other.
A back pressure hole 54 that short-circuits the valve 50 is formed in the valve 50.

The connecting bolt 47 is connected to one end of a swinging link 55 via a pin 48 , the intermediate portion of the link 55 is pivotally supported to the fuselage via a pin 56 , and the other end of the link 55 is connected via a wire 57 . and is connected to the link mechanism 30.

This link mechanism 30 has a first swing link 60 whose base end is pivotably supported on the fuselage body and which connects the top link 26 via a pin 59 in the middle.
and a second swing link 6 whose intermediate portion is pivotably supported by the fuselage body and whose one end is connected to the wire 57.
2, and an intermediary link 65 that connects the tip of the first swing link 60 and the other end of the second swing link 62 via pins 63 and 64, and is based on the second swing link 62. A reference value setting lever 67 is provided near the operation section for biasing a float ground pressure adjustment spring 66, which is a setting device, and adjusting the tension spring force of the spring 66 to set a reference value for the float ground pressure. Further, the intermediate portion of the lever 67 is swingably supported on the body via a pin 68, and the lower end of the lever 67 and the second swing link 6
2 intermediate tank 65 is attached to the outside of the connection point with spring 6.
6 is stretched, and the upper end operating side of this lever 67 is engaged with the notch 70 of the spring pressure adjusting plate 69. By adjusting the amount of movement of the lever 67, the spring pressure is changed and detected via the top link 26. It is configured to set a load reference value for the planting section 16.

As is clear from the above, in a device in which the planting section 16 is mounted so as to be freely raised and lowered by the link mechanism 17 which is a planting section support member, the back pressure adjustment is a load sensor that detects changes in the load of the planting section 16. valve 4
2, and a reference value setting lever 67, which is a manual operating tool for changing the load reference value of the planting section 16, is provided, and the lever 67 can be adjusted by hand operation by the operator in the driver's seat 13 due to changes in field hardness, etc. The valve 42 is operated to change the load reference value to properly operate the valve 42, and the cylinder 38 is configured to stably control the planting depth.

The present invention is constructed as described above, and as shown in FIG. valve 4
1 and the throttle valve 4 to the lifting cylinder 38 between the valve 42
4 and the switching valve 41, and the float 2
1 automatically adjusts the ground load of the float 21.
When the ground pressure is at the set value, the pressure oil discharged from the hydraulic pump 40 is returned to the tank 43 via the pressure reducing valve 50, and a constant hydraulic pressure is applied to the lifting cylinder 38 via the throttle valve 44. , the planting section 16 is maintained at a constant height.

Furthermore, if the surface of the field where the rice planting work is to be performed is relatively soft, the reference value setting lever 67 is moved in the direction of the solid line arrow in FIG.
The detection load reference value is made small, and the ground pressure of the float 21 is made small to prevent the float 21 from pushing mud. If the surface of the field is relatively hard, move the setting lever 67 in the direction of the broken line arrow in FIG. ,
By increasing the ground pressure of the float 21, the float 21
The mud leveling effect is fully activated.

During the rice planting work, for example, the seedling stand 18 is supplied with spare seedlings, and as the amount of seedlings increases, the seedling stand 18 is
becomes heavy, the lower link 25 rotates using the pin 27 as a fulcrum in the direction of stretching the spring 37, displacing the seedling stand 18 in the direction of tilting the top ring 26, the link mechanism 30, the wire 57, and the swing link. By retracting the operation shaft 46 via the throttle valve 55 and increasing the spring pressure of the pressure reducing spring 49 to increase the throttle oil pressure of the pressure reducing valve 50, pressure oil from the pump 40 is applied to the cylinder 38 via the throttle valve 44. , the lift arm 33 is rotated upward to rotate the lower link 25 upward in the direction of raising the seedling stand 18, and when the hydraulic pressures of the cylinder 38 and the pressure reducing valve 50 are balanced, that is, the ground pressure of the float 21 is reduced. When the pressure is returned to the set pressure, the cylinder 38 stops, supports each link 25, 26 in a fixed state, and continues the rice planting operation at a constant seedling planting depth.

On the other hand, if the seedling platform 18 becomes lighter due to a decrease in the number of seedlings loaded on the platform 18, the spring 3
The lower link 25 rotates using the pin 27 as a fulcrum in the direction of shrinking the seedling table 18, and moves the ink mechanism 30 via the top link 26 to the slack side of the wire 57 against the spring 66. By displacing the operating shaft 4
6 is advanced, the spring pressure of the pressure reducing spring 49 is weakened, the throttle oil pressure of the pressure reducing valve 50 is lowered, the pressure oil in the cylinder 38 is returned to the tank 43 via the throttle valve 44 and the pressure reducing valve 50, and the lift arm 33 is lowered. Rotate the lower link 25 in the direction to lower the seedling stand 18.
When the hydraulic pressure of the cylinder 38 and the pressure reducing valve 50 are balanced, that is, when the ground pressure of the float 21 is increased and returned to the set pressure, the cylinder 38 stops and the rice planting operation is performed at a constant planting depth. sustain.

Furthermore, when the weight of the seedlings on the seedling platform 18 and the force of the spring 37 are balanced, for example, if the field becomes deep and the float 21 is pushed up by muddy soil, and the ground pressure of the float 21 becomes high, the pin 28 The seedling platform 18 is displaced in the direction of falling down using the seedling platform 18 as a fulcrum, and the operation shaft 46
The lift arm 33 and the lower link 25 are rotated upward via the cylinder 38, and the seedling stand 18 is displaced in the direction in which the cylinder 3 is raised.
8 and the hydraulic pressure of the pressure reducing valve 50, float 2
Return the ground pressure in step 1 to the set value and continue rice planting at a constant planting depth.

On the other hand, when the field becomes shallow and the float 21 descends and the ground pressure of the float 21 becomes low, the seedling platform 18 is displaced in the direction of standing up using the pin 28 as a fulcrum, and the weight of the seedling platform 18 is reduced. Similarly, the operation shaft 46 is advanced against the spring 66, the pressure oil in the cylinder 38 is returned to the tank 43, the lift arm 33 and the lower ring 25 are rotated downward, and the seedling stand 18 is displaced in the direction of falling down. The hydraulic pressures of the cylinder 38 and the pressure reducing valve 50 are balanced, the ground pressure of the float 21 is returned to the set value, and the rice planting operation is continued at a constant planting depth.

As described above, the present invention raises and lowers the planting section 16 by increasing and decreasing the float grounding load due to changes in the amount of seedlings on the seedling platform 18 and the grounding pressure of the float 21, and the surface of the field where the rice planting work is performed is made soft and hard. The tension spring force of the spring 66 is adjusted according to the lever 67, and the ground pressure of the float 21 is changed.By installing the lever 67 near the driver's seat 13 in FIG. The detected load reference value of the planting section 16 can be changed via the lever 67, and the displacement amount of the top link 26 can be increased and the lever 67 can be operated via the link mechanism 30, that is, the first and second swing links 60, 62. It is easy to reduce the force, and it can be installed as a unit 71 with the back pressure adjustment valve 42 and the release switching valve 45 integrally with the switching valve 41 at any location such as the mounting position of the switching valve 41. etc., and can be made more compact.

By biasing the reference value setting lever 67 with the tension spring 66' shown in the virtual line state in FIG. 3, the spring force of the tension spring 66' tensioned on the second swing link 62 is offset, This makes it possible to further reduce the operating force of the lever 67.

"Effects of the Invention" As is clear from the above embodiments, the present invention provides a load sensor for detecting changes in the load of the planting part 16 in an apparatus in which the planting part 16 is movably raised and lowered by the planting part support member 17. 42 and a manual operation tool 67 for changing the load reference value of the planting section 16,
Even if the field hardness changes, the operator in the driver's seat operates the manual operating tool 67 to change the load reference value, so the output of the sensor 42 can always be appropriately determined. It is possible to prevent the planting depth from being changed due to changes in field hardness, it can be handled more safely than in the past, and the detection function of the sensor 42 can be easily improved.

[Brief explanation of the drawing]

FIG. 1 is a schematic side view of a riding rice transplanter showing an embodiment of the present invention, FIG. 2 is a plan view thereof, FIG. 3 is an explanatory diagram of the operation, and FIG. 4 is a sectional side view of the main parts. 16... Planting part, 26... Top link (planting part support member), 42... Back pressure adjustment valve (load sensor), 66... Float ground pressure adjustment spring (reference setter).

Claims (1)

[Claims] 1. In a device in which the planting section 16 is movably raised and lowered by a planting section support member 17, a load sensor 42 that detects changes in the load of the planting section 16 and a manual operation that changes the load reference value of the planting section 16 are provided. A float ground load adjustment device for a rice transplanter, characterized in that a tool 67 is provided.